Shaft-straightening machine.



T. J. PAINB, DEOD,

J. A. PAINE, ADMINISTRATRIX.

SHAFT STRAIGHTENING MACHINE.

APPLIOATION FILED APRJG, 1912. 1037, v Patented Sept. 3, 1912.

COLUMIM FLANOOIAPH C0,, WAIKINM D. C.

UNITED STATES PATENT OFFICE.

TIMOTHY J. PAINE, DECEASED, LATE OF WATERTOWN, MASSACHUSETTS, BY JULIA A. PAINE, ADMINISTRATRIX, OF WATERTOWN, MASSACHUSETTS.

SHAFT-STRAIGHTENING MACHINE.

Specification of Letters Patent.

Patented Sept. 3,1912.

To all whom it may concern:

Be it known that TIMOTHY J. PAINE, deceased, a citizen of the United States, and formerly residing at Watertown, in the county of Middlesex and State of Massachusetts, of whose estate I, JULIA A. PAINE, am legal administratrix, did invent a new and useful Improvement in Shaft-Straightening Machines, of which the following is a specification.

This invention relates to improvements in devices for straightening shafts which have become bent by accident or otherwise and relates particularly to such devices when used for the straightening of crank shafts combining several cranks, as used in internal combustion engines.

The object of this invention is to provide means for securely holding a crank shaft by any two of its journal bearings, and applying the pressure necessary to straighten the shaft at any one of three or more points around said shaft and in a radial direction, and without the necessity of' rotating the shaft previously supported upon V-pointed centers.

In this device the desired objects are obtained by means of the mechanism illustrated in the accompanying drawing, in which- Figure 1 is an end elevation of the device with the supporting and clamping blocks omitted; Fig. 2 is a front elevation complete; and Fig. 3 is an end elevation of one of the supporting and clamping blocks.

Similar letters refer to similar parts throughout the several views.

Heretofore it has been customary to support the shaft to be straightened upon the V-pointed centers of a lathe, or similar machine, and rotate it slowly, marking with chalk the points where its cylindrical surface projected farthest from the center of rotation. Having ascertained this, any ordinary means, as the blows of a hammer, the force exerted by a lever and fulcrum, etc., was applied in the effort to force the part back to its normal position and the operation of rotation and marking, and straightening repeated until the desired effect was produced. This process is slow and tedious and not always satisfactory. In the device herein illustrated and described the operation is much more quickly and satisfactorily performed.

A is the bed of the machine, here shown supported upon the legs B B resting upon the floor, although said bed may be supported in any other convenient manner, as

upon a special wooden bench or ordinary work bench. This bed is planed to a true surface on top and the projecting edges planed true to the form shown, although the edges may be made with inclined surfaces forming a dove-tail. Fitted to and sliding freely upon the bed A are the two supporting and clamping blocks 0 C, and the central straightening head F. The blocks C are of the form shown in Fig. 3, the top being formed with V-shaped grooves adapted to receive the bearings of the crank shaft to be straightened. The clamping bar D is pivoted at d and its front end rigidly secured by the swinging yoke E, pivoted to the block C as shown, and carrying the clamping screw 6 for securing it.

The straightening head consists of a base.

F, and the top segment G, pivoted at g, and its front end secured in position by the pivoted yoke H, carrying the clamping screw h.

The construction and operation of the yokes' E and H are identical. In the base F and top segment G are radial, dove-tail slots adapted to receive the sliding straightening blocks J J J, the inner ends of which are formed with V-shaped slots adapted to embrace cylindrical surfaces as shown. The blocks J are held in place and moved to and from the center by the pressure screws K K K, operated by the sliding levers L L L, having the right-angle handles Z Z Z,

formed upon them for convenience of operating.

The operation of this device is as follows: Referring particularly to Fig. 2, the supporting blocks C C and the straightening head F are placed in proper position to accommodate the crank shaft M, which is placed in proper position shown and the straightening blocks J J J withdrawn so as to be very close but not in contact with the center bearing 0. The crank shaft is then rotated and the amount of clearance between the bearing and the straightening blocks noted. The clamps D of the supporting blocks G C are then closed and secured by the yokes E E. The nature of the deflection of the crank shaft being known the proper straightening block J may be forced against it by the pressure screw L and the deflection corrected. Should one straightening block not have the desired effect either one of the remaining two blocks may be brought into use. hen the shaft is supposed to be straight it is unclamped and again tested by being rotated, and the work proceeded with as before. Should the deflection prove to have been a compound one, involving the bearings, m n 0 p and q to an unequal degree or from different directions, each bearing must be dealt with as just described for the center bearing 0. Thus if the bearing 71- is at fault the supporting block at the left will remain in the position shown, the straightening head F will be moved to the bearing a and then proceeded with as before. A similar method is used, for each of the other bearings until all the bearings of the crank shaft are in perfect alinement.

The top of the bed A being finished straight and true provides a proper support for the use of'the machinists surface gage, whose pointer may be brought to the under or upper side of either of the bearings to prove their correctness of alinement, instead of rotating the crank shaft for that purpose.

By the use of this mechanism in the manner described or by similar methods which will readily suggest themselves to the me chanic, crank shafts for multiple cylinder engines may be readily and quickly straightened whether the deflection is between adjacent cranks comprising one or more pairs; or a general deflection throughout the entire length. And these various defects can all be corrected without removing the crank shaft fro-mthe straightening machine. Thus the operation that formerly required four or five hours to perform, may be satisfactorily performed in about half an hour.

That I claim as new and desire to secure by Letters Patent is:

1. In a shaft straightening device the combination of two supporting blocks having V-shaped grooves in their top surfaces and means for clamping cylindrical shafts laid in said grooves, said supporting blocks being adapted to slide upon a supporting bed; a straightening head adapted to slide upon a supporting bed and consisting essentially of two or more radially sliding pressure blocks, pressure screws for forcing said blocks toward the center of said head, a base adapted to receive two of said pressure blocks and screws, a segment one end of which is pivoted to said base and means for clamping the opposite end to said base, said segment being adapted to receive one or more pressure blocks and screws; with a bed adapted to receive and support said supporting blocks and straightening head, substantially as described and for the purposes specified.

2. In a shaft straightening device, a straightening head consisting essentially of a base and a pivoted segment adapted to be clamped to said base, three or more radially sliding blocks screws for operating said blocks, shaft supporting blocks having V- shaped grooves on their top surfaces and means for clamping cylindrical shafts therein, in combination with a bed adapted to receive and support said straightening head and supporting blocks and permitting them to slide freely thereon, as and for the purposes described.

3. In a shaft straightening device, the combination of shaft support-ing blocks hav ing Vshaped grooves 011 their top surface, means for clamping a cylindrical shaft in said grooves; a straightening head having a plurality of radially disposed pressure blocks and actuating screws, with a bed adapted to support said shaft supporting blocks and straightening head and adapted to permit them to slide freely thereon, substantially as and for the purposes specified.

JULIA A. PAINE,

Arlminis'tratrw of the estate 0 Timothy J.

Paine, deceased. Witnesses:

ELDORA TrIoMrsoN, LOUISE P. ELLIOTT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

